Rolling mill



Dec. 27, 1932.

Filed Nov. 23, 1929 I5 Sheets-Sheet 1 Q 3 MM @W @N I I.

llll-Y Z n 2 4: w s LL: I IF 1 WM 9% mm QM INVENTOR Dec. 27, 1932. R,SHOVER 1,891,955

ROLLING MILL FiledNov. 23, 1929 s Sheets-Shae? 2 Dec. 27, 1932.

B. R. SHOVER ROLLING MILL 3 Sheets-Sheet 3 Filed Nov. 23. 1929 PatentedDec. 27, 1932 UNITED STATES PATENT OFFICE BARTON R. SHOVIB, OFPITTSBURGH, PENNSYLVANIA, ASSIGNDR TO ALLEGHENY STEEL COMPANY, ACORPORATION OF PENNSYLVANIA ROLLING MILL Application filed November 23,1929. Serial No. 409,240.

This invention relates to rolling mills and particularly to mills forrolling metal sheets, strips, plates and the like.

An object of this invention is to control the rolling pressures to whichsheets are subjected during the rolling operations.

Another object of the invention is to provide a rolling mill that shallbe particularly adapted to the method, disclosed in the United StatesLetters Patent No. 1,367,015,

granted to V. B. Browne, of controlling the grain growth in magneticalloy sheets.

A still further object of the invention is to provide an improvedrolling mill of the type shown in the patent to Browne No. 1,367,015 andemployed for carrying out the method disclosed in said patent.

As stated in the aforesaid patent to Browne No. 1,367,015, the pressureto which the alloy sheets are subjected during the rolling operations,is controlled in accordance with the degree of heat used in obtaining acertain grain structure, so that the strain produced in the sheets issuch that the grain in the finished sheet after annealing is of a sizepredetermined to be the proper size to give to such sheets the desiredpermeability with permissible hysteresis and eddy current losses.

The invention herein disclosed comprises the novel arrangement andcombination of parts substantially as set forth, and is particularladapted to control the pressures to whic magnetic alloy sheets, strips,plates and the like are subjected during the rolling operations.

For a better understanding of the invention, reference may be had to thefollowing description taken in conjunction with the accompanyingdrawings in which:

Figure 1 is a top plan view of a rolling mill arranged and constructedin accordance with the invention;

Fig. 2 is a front view in elevation,-partly in section, of the millshown in Fig. 1; and

Fig. 3 is a side view in elevation of the mill shown in Figs. 1 and 2.

Throughout the drawings and the specifica-' tionlike characters ofreference indicate like parts. j

In the drawings a rolling IIllll. designated yieldingly held apart bymeans of upper and lower bearing blocks 12 and 13 and a coil spring 14located between the blocks (see Figs. 2 and 3). p

' In order that the roll 5 may be adjusted to any predetermined positionwith respect to'the lower roll 6, the usual screw-downs 17 and 18 areprovided, the screw-downs being employed to force the roll 5 to anypredetermined position with respect to the roll 6 against the force ofthe resilient and yieldable means or springs 14 tending to separate andhold them in a normal operating relation or position. As shown thescrew-down 17 passes through the upper part of the housing 2 and hasscrew thread engagement therewith, such construction being common andwell known. y

In rolling magnetic alloy sheets the sheets are heat treated prior tothe rolling operations in order to obtain a predetermined grainstructure characteristic as set forth in the patent to Browne, No.1,367,015.

As set forth in the specification of this patent, it is necessary tocontrol the pressure imposed on the sheets by the rolls 5 and 6 at asubstantially constant value during the rolling operation for the reasonthat if the sheets are heated to a predetermined temperature prior tothe rolling operations and if during the rolling operations the pressureimpose on the sheets by the rolls is maintained at a substantiallypredetermined value, thegra-in structure of the finished sheets will besuch as is conducive to high permeability with pen missible hysteresisand eddy current losses.

As pointed out in the patent to Browne No. 1,367,015, the alloy sheetsare heat treated and rolled at a predetermined temperature- However, itoften-happens that' the sheets may not be of uniform temperaturethroughout and as a consequence of which certain sections of ithe sheetswill be relatively soft and others will be relatively hard. Because ofthe variations in hardness of the sheets, the rolling pressures willvary. Also, it frequently happens that the temperature of the entiresheets drops below the predetermined value at which they should berolled thereby causing the sheets to be harder than they would be ifrolled at the proper temperature. This increased hardness causes therolling pressures to be increased above the value which will give theproper grain.

' growth characteristic. The grain structure characteristic of thesheets will be uniform if the rolling pressures are maintained constantthroughout.

Therefore, in order to so control the rolling pressure that the finishedsheets shall acquire the proper grain structure during the rolling.operations, the upper part of the housing'3 is provided with aninternally screw threaded bushing 19. As shown the screw-down 18 hasscrew-thread engagement with the internally screw-threaded bushing 19.For.

best results the pitch of the screw threads in the bushing 19 isrelatively steep or of such a pitch as will permit the screw down 18 toautomatically turn in response to an upward force being imposed on thelower end thereof by the upper roll 5. This upward force varies inaccordance with the changes or variations in the rolling pressure.

At this point it is to be noted that thrust blocks 21 and 22 areinterposed between the lower end of the screwdowns 17 and 18 and thenecks 7 and 8 of the roll 5, the blocks being provided with arc-uatebearing members 23 and 24, respectively, (see Figs. 2 and 3) which rideon the necks of the roll 5.

In order that the upward force of the roll 5 against the screw-down 18,which causes it to turn to permit upward movement of the roll, may alsocause the screw-down 17 to turn simultaneouslywith the screw-down 18,the screw-downs 17 and-18 are provided with pinions 26 and 27 that meshwith a rack 28. The rack 28 may be guided and held in meshing relationwith the pinions 26 and 27 by means of guide brackets 29 and 30 that aremounted on the top of the respective housings 2 and 3 and securedthereto by means of bolts or other suitable means. The mechanismcomprising the rack and the pinions on the screws is well known in theart.

The movement of the rack 2-8 in response to a turning movement of thescrew-down 18 is yieldingly opposed by a piston 3-lwhich is mounted in acylinder 32, the piston operating against the pressure of a fluidentering the cylinder through a pipe connection 33.

The pressure of the fluid entering the cylinder 32 through the pipe 33is preferably .maintained at a constant value by an accumu-- asindicated in Fig. 1. The cylinder 32 may be mounted on a bracket 35which is secured to the upper portion of the housing 3 by bolts 36 orother suitable means.

The movement of the,rack 28 in the direction indicated'by the arrow 37may be limited by an adjustable stop member 38 which has screw-threadengagement with a bracket or standard 39'. as shown in Figs. 1 and 2.The bracket or standard 39 may be secured to the upper portion of thehousing 2 by means of bolts 40 or other suitable means. The adjustablestop member 38 may be adjusted to any predetermined position by means ofa hand wheel 41.

Inorder that adjustment of the screwdown 18 may be made so that the endsof the roll 5 may be brought into exact alignment, the bushing 19 isprovided with an annular gear 42 at its upper end, a construction alsowell known in the art, (see Figs. 1 and 2) that meshes with a worm 43.The worm 43 is mounted on a shaft 44 that extends through a bracket 45secured to the housing 3. The

shaft 44 may turned by means of a hand wheel 46 secured to the outer endof the shaft.

By turning the hand wheel 46 in the proper direction, the screw-down 18may be moved up or down until the ends of the roll 5 are equally spacedwith reference to the ends of the roll 6. A

In the rolling of steel sheets of the char- Y sheets are between therolls. If provision were not made for permitting the roll 5 toautomatically move upwardly when the hard seciions of the sheets passbetween the rolls, the hard sections would be subjected to a greaterstraln than the softer sections.

Therefore, as stated in the above patent to Browne, the grain structureof the harder sections of the sheets will not be the same as the gramstructure of the softer sections because the rolling pressures will notbe equal or uniform through the lengths of the sheets. As the alloysheets pass between the rolls 3 5 and 6, the roll 5 will be forcedupwardly when the rolling pressure exceeds a predetermined value. Sincethe upward force will cause the screw-down 18 to turn in such adirection that, the pressure will be relieved, the

screw-down 17 will also turn because the pinlae ions of the screw-downsare mechanically connected by means of the rack 28. Since the upwardmovement of the roll 5 is yieldingly opposed by the piston 31 actingagainst the fluid 5 pressure in the cylinder, upward movement of thescrew-downs will be' gradual rather than abrupt.

When' the rolling pressure has been re lieved, the screw-downs will beautomatically operated to their adjusted positions by virtee of the factthat the pressure of the cylinder biases the piston 31 towards the end3% of the cylinder. I

By controlling the rolling pressure imposed on the sheets to be rolledin the manner set forth above and by the. apparatus employed for thatpurpose, the grain structure of the sheets will be uniform and of thedesired value. Since the grain structure is of the desired value, thepermeability of the sheets will be of the proper predetermined value,which permeability may be obtained without sacrificing that quality ofthe alloy sheets which tend to maintain the hysteresis and the eddycurrent losses at rmissible values.

While various modi cations and changes may be made in the mill hereinshown and described without departing from the spirit and the scope ofthe invention, it is to be understood that only such limitations shallbe placed on the invention as are imposed by the prior art and theappended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a rolling mill having upper and lower rolls and a screw-down foreach end of the upper roll, and means for simultaneously operating theother screw-down in response to operation of the first mentionedscrew-down comprising a pinion on each-screw-down, a rack disposed tomesh with said pinions and means for operating one of said screw-downsresponse to an excessive vertical pressure against said upper roll, andmeansyieldably limiting the movement of said rack in one direction, andmeans positively limiting the movement of said rack in the otherdirection.

2. In a rolling mill having upper and lower rolls and a screw-down foreach end of the upper roll, and means for simultaneously 0peratin theother screw-down in response to operation of the first mentionedscrew-down comprising a pinion on each screw-down, a rack disposed tomesh with said pinions, means for operat ng one of said screw-downs inresponse to an excessive vertical pressure against said upper roll,means positioned between said upper and lower rolls yieldably holdingthem in a normal operating relation, and means for yieldingly limitingthe movement of said rack in one direction, and means for positivelylimiting the movement of said rack in another direction.

3. In a rolling mill having upper and lower rolls and a screw-down foreach end of the upper roll, and means for simultaneously operating theother screw-down in response to operation of the first mentionedscrew-down comprising a pinion 011 each screw-down, a rack disposed tomesh with said pinions and means for operating one of said screwdowns inresponse to an excessive vertical pressure against said upper roll,means positioned between the necks of said rolls yieldingly holding themin a normal operating relation, and pressure responsive means foryieidingly controlling the movement of said rack in one direction, andmeans for positively limiting the movement of said rack in anotherdirection.

d, In a roliing opposed housings, an internally threaded bushing in oneof said housings, a screw-down in the other housing, a screw-down havingscrew thread engagement with said bushing, pinions on each of saidscrew-downs, a rackmeshing with said pinions, means for turning saidbushing and thereby adjusting one screw-down with respect to the other,so that the ends of the upper roll may be brought into exact alignment.said bushing being provided with an annular gear at its upper end, saidmeans in cluding a worm gear mounted on a handwheel controlled shaft andcooperating with said annular gear, and a pressure control device foryieldingly opposing the movement of said rack in one direction, andmeans positively limiting the movement of said rack in anotherdirection.

5. In a rolling mill having upper and lower rolls, and a screw-down foreach end of the upper roll, means for operating one of said screw-downsin response to an excessive vertical pressure against one of said rollsand means for simultaneously operating the other screw-down in responseto operation of the first mentioned screw-down, and means yieldablylimiting the movement of said screwdowns in an upward direction andpositively limiting the maximum movement of said screw-downs in theopposite direction.

, 6. In a rolling mill having upper and lower rolls, and a screw-downfor each end of one of said rolls, and means for simultaneouslyoperating one screw-down in response to operation of another screw-downcomprising a pinion on each screw-down, means positioned-between theupper and lower rolls yieldably holding them apart in a normal operatingrelation, a rack disposed to mesh with said pinions and means foroperating one of said screw-downs in response to an excessive verticalpressure against said roll, and means yiel-dably limiting the movementof said rack in one direction, and means positively limiting themovement of said rack in another direction.

7. In a rolling mill, opposed housings, an internally threaded bushingin one of said housings, a screw-down in the other housing, a screw-downhaving screw thread engagement with said bushing, pinions on each ofsaid screw-downs, a rack meshing with said pinions,. and means forturning said bushing to adjust said screw-downs, means for yieldinglylimiting the movement of said rack in one direction and means forpositively limiting the movement of said rack in another direction.

8. In a rolling mill having upper and lower rolls and a screw down foreach end of the upper roll, means for simultaneously operating one screwdown in response to operation of another screw down, including a pinionon each screw down, a. rack disposed to mesh with said pinions, meansyieldably holding said rolls in a normal separated and operatingrelation,means automatically raising one or both of said screw downs inres onse to an excessive vertical pressure against the upper roll andlowering said screw downs when said upper roll is relieved from saidexcessive pressure, said lowering bein limited by said resilient means,and means or yieldingly limiting the movement of said rack in onedirection, and for positively limiting the movement of said rack inanother direction.

9. In a rolling mill having upper and lower rolls and a screw down foreach endof the upper roll, means for simultaneously operating one screwdown in response to an operation of the other screw down, including apinion on each screw down, a rack disposed to mesh with said pinions,means for raising one or both of said screwdowns in response to anexcessive vertical pressure against the upper roll, means for aiding alowering of said screw downs when said upper roll is relieved from saidexcessive pressure, means for yieldingly limiting the movement of saidrack in one direction, and means for posi-. tivel limiting the movementof said rack in anot er direction.

10. In a rolling mill having upper and lower rolls, and a screw-down foreach end of the upper. roll, means for operating one of said screw-downsin response to an excessive vertical pressure. against the upper roll,means for simultaneously operating the other screw-down in response tooperation of the first-mentioned screw-down, means positioned betweensaid upper and lower rolls yieldably holding them in a normal operatingrelationship, and additional means for yieldably limiting the movementof said screwdowns in onev direction and positively limiting themovement of said screw-downs in the opposite direction.

11. In a rolling mill having up er and lower rolls, and a screw-down foreac end of the upper roll, means holding said rolls in 8. normaloperating relationship, means for raising said screw-downs in responseto an excessive vertical pressure against the upper roll and forlowering said screw-downs whezi sald upper roll is relieved of saidexcessive pres sure, said lowering being limited by said holding means,and additional means for yieldably limiting the movement of saidscrewdowns in one direction and positively limiting the movement of saidscrew-downs in another direction.

12. In a rolling mill having a pair of rolls and suitable screw-downtherefor, means normally holding said rolls in a given relationship withrespect to each other, means for operating said screw-downs in responseto an excessive pressure upon said rolls, and additional means foryieldably limiting the movement of said screw-downs in one direction andpositively limiting the movement of said pinion on each screw-down, arack'disposed to mesh with each pinion, means yieldably holding saidrolls in a normal operating relation, means automatically raising one orboth of said screw -downs in responsive to an excessive pressureagainstthe upper roll and automatically lowering said screw-downs whensaid upper roll is relieved from said excessive pressure, said loweringbeing limited by said resilient means, a pressurecontrolling device foryieldably opposing movement of said rack in one directlon, and meanspositively limiting movement of said rack in another direction.

14. In a rolling mill having upper and lower rolls, the combination ofmeans c0- operating with the upper roll and yieldably holding it nearits normal operating position and limiting upward movement thereof, saidmeans including means for raising the upper roll when the pressurebetween said rolls reaches an excessive value and lowering the upperroll'when said pressure. reaches 8. normal value, additional meanspositively limiting the maximum lowering of the upper roll, andresilient means normally positioning the upper roll and being anintermediary between said yieldable'means and said positive means, sothat the rolls will be held in a normal relation when the pressure is ata normal value, and that a piece being rolled willbe subjected to aconstant rolling pressure irrespectiv'e of the hardness of a givenportion thereof for imparting a uniform grain structure thereto.

15. In' a rolling mill having upper and lower rolls, the combination ofscrew-downs for each end ofthe upper roll, said screwthey will rotateupon a pressure exerted axially thereof, and means cooperating with saidscrew-downs at right angles to the axes thereof for yieldably pressingsaid screwdowns in a roll-compressing direction, and means cooperatingwith the necks of said upper roll for I101 ing it in a normal operatingrelation with respectto the lower roll, said upper roll being upwardlymovable against said yieldable means when an excessive pressure isencountered during a rolling operation, and said roll being returnableto an original operating position when said excessive ressure isrelieved, and additional means limiting the distance to which the up-:ner roll is lowered, so that the rolls will be held a normal relationwhen the pressure is at e nermei value, and that a piece being rolledwill subjected to a-constant rolling pressure irrespective of thehardness of a given portion thereof for imparting a uniform grainstructurethereto,

testimony whereof, I have hereunto subscribed my name this 22nd day ofNovember,

BARTON R. SHOVERt

